A sheet feeder retrieves a single sheet from a stack of sheets and provides the single sheet to a device. Examples of devices that utilize sheet feeders include printers, copiers, scanners, facsimile machines, and multifunction devices.
One example of a conventional sheet feeder includes three rollers that cooperate to carry out the function of the sheet feeder. The three rollers are often referred to as pick, feed, and separator rollers. The pick roller contacts one of the sheets in a stack of sheets and rotates to urge the contacted sheet between the feed and separator rollers. Occasionally, the contacted sheet adheres to an adjacent sheet and both sheets move towards the feed and separator rollers.
The feed roller rotates to advance the contacted sheet. The separator roller rotates in a direction opposite the feed roller to help prevent an adhering sheet from being advanced with the contacted sheet. The contacted sheet advances against the rotation of the separator roller until the torque reaches a threshold. Then, the separator roller reverses direction. This action causes the separator roller to wear at a greater rate than the pick and feed rollers. Consequently, the separator roller must be replaced more frequently than the pick and feed rollers.